[PATCH 13/26] bpfilter: switch bpfilter_ip_set_sockopt to sockptr_t
From: Christoph Hellwig <hch@lst.de>
Date: 2020-07-23 06:11:58
Also in:
bpf, bridge, linux-bluetooth, linux-can, linux-crypto, linux-hams, linux-s390, linux-sctp, lkml, lvs-devel, mptcp, netfilter-devel
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), networking [general], networking [ipv4/ipv6], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
This is mostly to prepare for cleaning up the callers, as bpfilter by design can't handle kernel pointers. Signed-off-by: Christoph Hellwig <hch@lst.de> --- include/linux/bpfilter.h | 6 +++--- net/bpfilter/bpfilter_kern.c | 6 +++--- net/ipv4/bpfilter/sockopt.c | 8 ++++---- net/ipv4/ip_sockglue.c | 3 ++- 4 files changed, 12 insertions(+), 11 deletions(-)
diff --git a/include/linux/bpfilter.h b/include/linux/bpfilter.h
index 9b114c718a7617..2ae3c8e1d83c43 100644
--- a/include/linux/bpfilter.h
+++ b/include/linux/bpfilter.h@@ -4,9 +4,10 @@ #include <uapi/linux/bpfilter.h> #include <linux/usermode_driver.h> +#include <linux/sockptr.h> struct sock; -int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval, +int bpfilter_ip_set_sockopt(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen); int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen);
@@ -16,8 +17,7 @@ struct bpfilter_umh_ops { struct umd_info info; /* since ip_getsockopt() can run in parallel, serialize access to umh */ struct mutex lock; - int (*sockopt)(struct sock *sk, int optname, - char __user *optval, + int (*sockopt)(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen, bool is_set); int (*start)(void); };
diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c
index 00540457e5f4d3..f580c3344cb3ac 100644
--- a/net/bpfilter/bpfilter_kern.c
+++ b/net/bpfilter/bpfilter_kern.c@@ -60,17 +60,17 @@ static int bpfilter_send_req(struct mbox_request *req) } static int bpfilter_process_sockopt(struct sock *sk, int optname, - char __user *optval, unsigned int optlen, + sockptr_t optval, unsigned int optlen, bool is_set) { struct mbox_request req = { .is_set = is_set, .pid = current->pid, .cmd = optname, - .addr = (uintptr_t)optval, + .addr = (uintptr_t)optval.user, .len = optlen, }; - if (uaccess_kernel()) { + if (uaccess_kernel() || sockptr_is_kernel(optval)) { pr_err("kernel access not supported\n"); return -EFAULT; }
diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c
index 9063c6767d3410..1b34cb9a7708ec 100644
--- a/net/ipv4/bpfilter/sockopt.c
+++ b/net/ipv4/bpfilter/sockopt.c@@ -21,8 +21,7 @@ void bpfilter_umh_cleanup(struct umd_info *info) } EXPORT_SYMBOL_GPL(bpfilter_umh_cleanup); -static int bpfilter_mbox_request(struct sock *sk, int optname, - char __user *optval, +static int bpfilter_mbox_request(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen, bool is_set) { int err;
@@ -52,7 +51,7 @@ static int bpfilter_mbox_request(struct sock *sk, int optname, return err; } -int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval, +int bpfilter_ip_set_sockopt(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen) { return bpfilter_mbox_request(sk, optname, optval, optlen, true);
@@ -66,7 +65,8 @@ int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, if (get_user(len, optlen)) return -EFAULT; - return bpfilter_mbox_request(sk, optname, optval, len, false); + return bpfilter_mbox_request(sk, optname, USER_SOCKPTR(optval), len, + false); } static int __init bpfilter_sockopt_init(void)
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 42befbf12846c0..36f746e01741f6 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c@@ -1414,7 +1414,8 @@ int ip_setsockopt(struct sock *sk, int level, #if IS_ENABLED(CONFIG_BPFILTER_UMH) if (optname >= BPFILTER_IPT_SO_SET_REPLACE && optname < BPFILTER_IPT_SET_MAX) - err = bpfilter_ip_set_sockopt(sk, optname, optval, optlen); + err = bpfilter_ip_set_sockopt(sk, optname, USER_SOCKPTR(optval), + optlen); #endif #ifdef CONFIG_NETFILTER /* we need to exclude all possible ENOPROTOOPTs except default case */
--
2.27.0